How a Stranger Used One Text Message to Steal My Entire Digital Life -- Time

[AZJonnie]

6. So if you are traveling and spend a decent amount of $ at a city far from where you are 99% of the time

And it appears legit and says "Did you just spend $857.38 at Far Flung Trading Company" and you know you did, like 10 seconds earlier, and the purchase was declined, and it makes sense this might trigger the credit card company to flag the purchase (as in this case), you refuse to reply to it, on the premise that it would be fiscally irresponsible to do so? I'm trying to reckon "how so"? Even if it was fake, what is the risk? Not saying you're wrong about it, I'm trying to see if there's something I've missed/not thought about?

About a year ago someone leveraged my Playstation Plus account to buy a bunch of games totaling over $300 and I got a fraud alert and said "No, I did not" and it was all legit (someone really had gotten hold of my password or some such), and soon after got my money (which IIRC was only on hold, not actually charged IIRC) back.

I guess what I mean is apart from the fact you'd be letting a marketer know that this phone number links to a real person, what is the 'exposure' involved in simply affirming or denying a purchase in an amount at a place? What am I missing?